Whitelist-CGI.c

//
// compiled with arm-unknown-linux-gnueabi-gcc Whitelist-CGI.c -o Whitelist-CGI.cgi
//
#define sizearray(a)  (sizeof(a) / sizeof((a)[0]))

#include "stdio.h"
#include "unistd.h"
#include "stdlib.h"
#include "string.h"


#define QS_LEN 65536


int main(void)
{

    //Initialise variables for whitelist call
    char *var_d;
    char *var_b;
    char *var_t;
    char *var_s;
    char *var_a;

    char *data;
    char *token;
    char *key;
    char *value;

    FILE *ptr_file;
    char buf[1000];

    //Allocate memory to variables
    data = malloc(QS_LEN);
    token = malloc(QS_LEN);
    key = malloc(QS_LEN);
    value = malloc(QS_LEN);

    var_d = malloc(QS_LEN);
    var_b = malloc(QS_LEN);
    var_t = malloc(QS_LEN);
    var_s = malloc(QS_LEN);
    var_a = malloc(QS_LEN);

    //Query request string and allocate values received to variables
    if (getenv("QUERY_STRING"))
    {
        token = strtok (getenv("QUERY_STRING"),"&");
        while (token != NULL)
        {
            sscanf(token, "%[^=]=%65536s", key, value);
            if ( compStr(key, "d", sizearray(key) ))
            {
                strcpy(var_d, value);
            }
            if ( compStr(key, "b", sizearray(key) ))
            {
                strcpy(var_b, value);
            }
            if ( compStr(key, "t", sizearray(key) ))
            {
                strcpy(var_t, value);
            }
            if ( compStr(key, "s", sizearray(key) ))
            {
                strcpy(var_s, value);
            }
            if ( compStr(key, "a", sizearray(key) ))
            {
                strcpy(var_a, value);
            }
            token = strtok (NULL, "&");
        }
    }

    FILE *fp;
    mkdir("/data/eureka", 0777);
    char path[1035];

    //Check if Whitelist bypass to Google is enabled
    fp = popen("EurekaSettings get WhiteList useSelection", "r");
    //error out if command fails
    if (fp == NULL)
    {
        printf("Failed to run command\n" );
        return 0;
    }
    //compare value of EurekaSettings
    while (fgets(path, sizeof(path)-1, fp) != NULL)
    {
        if(compStr(path, "1"))
        {
            //Bypass enabled, redirect to Google
            printf( "HTTP/1.1 302 Object moved\n" );

            //Are we doing a whitelist pull, or app lookup?
            if (strlen(var_a) != 0)
            {
                // v2 app lookup, push to googles server as they are not using our whitelist service
                // TO-DO: Find all calls used by stock google so we can mimmic it here. For sure d and b are used -dd
                printf( "Location: https://clients3.google.com/cast/chromecast/device/app?a=%s&b=%s&d=%s\n\n\n", var_a, var_b, var_d);
            }
            else
            {
                // doing normal whitelist pull
                //If all device variables provided pass onto google
                if ((strlen(var_b) != 0) && (strlen(var_s) != 0) && (strlen(var_d) != 0) && (strlen(var_t) != 0))
                {
                    printf( "Location: http://clients3.google.com/cast/chromecast/device/baseconfig?b=%s&d=%s&t=%s&s=%s\n\n\n", var_b, var_d, var_t, var_s);
                }
                else
                {
                    //Not all device variables provided, check for device version config and pass to google
                    if(strlen(var_b) != 0)
                    {
                        printf( "Location: http://clients3.google.com/cast/chromecast/device/baseconfig?b=%s\n\n\n", var_b);
                    }
                    else
                    {
                        //device config version not provided, proceed to google emulating 14651
                        printf( "Location: http://clients3.google.com/cast/chromecast/device/baseconfig?b=14651\n\n\n" );
                    }
                }
            }
        }
        else
        {

            //Are we doing a whitelist pull, or app lookup?
            if (strlen(var_a) != 0)
            {
                // v2 app lookup using eureka server
                // I hate doing this, but we need to have the hashed serial to test for a "test" device -dd
                ptr_file=popen("busybox sha1sum /factory/serial.txt | busybox awk '{ print $1 }'","r");
                while (fgets(buf,1000, ptr_file)!=NULL)
                {
                    printf( "HTTP/1.1 302 Object moved\n" );
                    printf( "Location: http://pwl.team-eureka.com/applist.php?applookup=true&a=%s&serial=%s\n\n\n", var_a, buf );
                }
                pclose(ptr_file);
            }
            else
            {
                //Normal whitelist pull
                //Redirect not present, present local whitelist
                printf( "HTTP/1.1 200 OK\n" );
                printf( "Content-Type: application/json; charset=utf-8\n" );
                printf( "Cache-Control: no-cache, no-store, max-age=0, must-revalidate\n" );
                printf( "Pragma: no-cache\n" );
                printf( "Expires: Fri, 01 Jan 1990 00:00:00 GMT\n" );
                printf( "Date: Sat, 23 Nov 2013 01:15:47 GMT\n" );
                printf( "Content-Disposition: attachment; filename=\"json.txt\"; filename*=UTF-8''json.txt\n" );
                printf( "X-Content-Type-Options: nosniff\n" );
                printf( "X-Frame-Options: SAMEORIGIN\n" );
                printf( "X-XSS-Protection: 1; mode=block\n" );
                printf( "Server: GSE\n" );
                printf( "Alternate-Protocol: 443:quic\n" );
                printf( "Transfer-Encoding: chunked\n\n" );

                //Read whitelist from file, print to web.
                FILE *ptr_file;
                char buf[1000];

                //If web is up, force update check
                ptr_file = popen("ping -c 1 -w 1 google.com > /dev/null ; echo $?", "r");
                while (fgets(path, sizeof(path)-1, ptr_file) != NULL)
                {
                    if (compStr(path, "0\n", sizearray(path) ))
                    {
                        system( "busybox sh /system/usr/share/eureka-apps/whitelist-sync/whitelist-sync > /tmp/whitelist-sync.log" );
                    }
                }

                //check if whitelist apps.conf exists in data (if not use system apps.conf)
                if(access("/data/eureka/apps.conf", F_OK) != -1 )
                {
                    ptr_file =fopen("/data/eureka/apps.conf","r");
                }
                else
                {
                    ptr_file=fopen("/system/usr/share/eureka-apps/configs/apps.conf", "r");
                }

                while (fgets(buf,1000, ptr_file)!=NULL)
                    printf("%s",buf);
                fclose(ptr_file);
            }
        }
    }

    pclose(fp);
    return 0;

}

//Function to compare 2 character arrays for string comparison
int compStr (const char *s1, char *s2, size_t sz)
{
    while (sz != 0)
    {
        // At end of both strings, equal.
        if ((*s1 == '\0') && (*s2 == '\0')) break;

        // Treat spaces at end and end-string the same.
        if ((*s1 == '\0') && (*s2 == ' '))
        {
            s2++;
            sz--;
            continue;
        }
        if ((*s1 == ' ') && (*s2 == '\0'))
        {
            s1++;
            sz--;
            continue;
        }

        // Detect difference otherwise.
        if (*s1 != *s2) return 0;
        s1++;
        s2++;
        sz--;
    }
    return 1;
}